An illustration of what the Philae lander will look like at work on Comet 67P/Churyumov-Gerasimenko. AOES Medialab/ESA hide caption

Part of the ALMA array on the Chajnantor plateau of Chile points skyward to the Milky Way, our own galaxy. The center of our galaxy is visible as a yellowish bulge crossed by dark lanes, which are themselves huge clouds of interstellar dust. José Francisco Salgado/ESO hide caption

Your direct connection with the stars and all of the space in between them. iStockphoto.com hide caption

Even if we find other life out there, in the depths of space, life here will still be a rare gem that must be worshipped and preserved at all costs. ESO hide caption

A bubble in space: Abell 39 marks the death of a star like the sun. Wind from the aging central star pushes into the surrounding interstellar gas, building up a dense shell that glows blue in this image. After 36 years of travel, the Voyager spacecraft is just now reaching the edge of the sun's own wind-blown bubble. WIYN/NOAO/NSF hide caption

This artist rendering provided by NASA shows Voyager 1 at the edge of the solar system. AP hide caption

Will we need to tread lightly, in deference to the locals, when finally do make it to Mars? Pat Rawlings/SAIC/NASA hide caption

Debris: friend or foe? Both! Illustration/NASA hide caption

Earthrise, seen from Apollo 8 as it circles the moon in 1968. NASA hide caption

An artist's imagination Saturn's orange moon Titan. Steven Hobbs/NASA hide caption

On its way to Jupiter, the Galileo spacecraft looked back and captured this remarkable view of Earth and the moon. The image was taken from a distance of about 3.9 million miles. NASA hide caption

An artist's impression of a gamma-ray burst, a powerful jet of energy lasting from less than a second to several minutes. The most powerful events in the universe, they are thought to be mostly associated with the explosion of stars that collapse into black holes. A. Roquette/ESO hide caption

Venus on the eastern limb of the Sun captured by TRACE satellite. NASA hide caption